Transmissions, such as vehicle transmissions, have one or more gear meshes that selectively transfer torque from an input shaft to an output shaft of the transmission. The gear meshes commonly require lubrication during transmission operation. The gear meshes and lubricant may be contained within a transmission case or housing, and a sump may be provided to collect the fluid and act as a reservoir.
Lubrication systems are used to circulate lubricant and provide sufficient a quantity of filtered lubricant to all the moving parts of a transmission. Several types of lubrication systems are known. For example, a system referred to as a splash system utilizes a splasher or dipper affixed to one or more of the moving traction parts within an internal cavity of the transmission case. The moving parts are cycled through lubricant within the sump during the movement of parts and lubricant is splashed about the internal cavity of the case. The splash may be diverted using internal features of the transmission such as veins or funnels that direct the flow of lubricant as it drains. Splash systems include a high volume of lubricant and may allow lubricant to slosh within the internal cavity. One problem with splash lubrication is that it is speed dependent. There can be centrifugal effects, hydrodynamic effects, and effects from the gears working as pumps that may reduce efficiency of the transmission.
Dry lubrication systems distribute lubricant differently compared to splash systems. In dry systems, a significantly smaller volume of lubricant is contained in a sump within the transmission. The lubricant is drawn out of the sump and diverted to the traction components as required. A complex series of tubes may be assembled in a dry system where each tube has particular shapes for diverting lubricant to specific locations within the transmission. The complex tubes may be steel tubes that are formed and joined to separate nozzles. Several different tubes may be assembled to a larger central tube, or may be joined to each other by a larger over-molded body. Assembly of a large number of customized parts is often expensive and may require complex tooling.
This disclosure is directed to solving the above problem and other problems as summarized below.